.travis.yml in cose-0.8.0 vs .travis.yml in cose-0.9.0

@@ -3,33 +3,24 @@
 cache: bundler
 
 rvm:
   - ruby-head
   - 2.7.0-preview1
-  - 2.6.3
-  - 2.5.5
-  - 2.4.6
+  - 2.6.4
+  - 2.5.6
+  - 2.4.7
   - 2.3.8
-  - 2.2.10
 
 gemfile:
   - gemfiles/openssl_head.gemfile
   - gemfiles/openssl_2_1.gemfile
   - gemfiles/openssl_2_0.gemfile
   - gemfiles/openssl_default.gemfile
 
-before_install: gem install bundler -v '~> 1.17'
+before_install: gem install bundler -v '~> 2.0'
 
 matrix:
   fast_finish: true
   allow_failures:
     - rvm: ruby-head
     - rvm: 2.7.0-preview1
-    - rvm: 2.2.10
     - gemfile: gemfiles/openssl_head.gemfile
-  exclude:
-    - rvm: 2.2.10
-      gemfile: gemfiles/openssl_head.gemfile
-    - rvm: 2.2.10
-      gemfile: gemfiles/openssl_2_1.gemfile
-    - rvm: 2.2.10
-      gemfile: gemfiles/openssl_2_0.gemfile